When wireless works the way it is supposed to, clinicians can be very, very happy with it.

"I love it," says internist Timothy Laing, MD. "I would not go to clinic without it." In fact, says Dr. Laing, a user of the University of Michigan’s wireless LAN, when he finds himself walking to clinic sans his wireless device, "I get the same sensation I get when I leave my credit card in a restaurant—I immediately turn on my heel and go back for it."

Certainly there’s plenty to love about technology that permits access to laboratory and other clinical data from virtually any location and from any device. But the technologies and tools to do so are neither fully developed nor widely deployed yet. Among the remaining challenges: the need to adapt traditional desktop applications for palmtop devices, varying data transmission speeds, interference and coverage issues, inadequate battery lives for some devices, higher costs, and incomplete security measures.

Wireless LANs

Today wireless access to laboratory and other clinical data tends to fall into two related but distinct areas. In a few locations, clinicians are finding that carrying small, ultraportable laptops with them as they see hospitalized patients gives them access to virtually all the clinical and administrative information they could get using a desktop computer. This access is possible thanks to a wireless technology that complies with an Institute of Electrical and Electronic Engineering standard known as 802.11b and that provides data as rapidly as typical office networks—that is, 10-11 megabits per second.*

But when clinicians are away from a health care facility, they must rely on any of several different cell phone technologies. These work relatively slowly, at about 10-14 kilobits per second, and have small screens and short battery lives in some cases.

More important, perhaps, is that cell phone coverage inside buildings is unreliable. "We have a nine-story hospital, a cancer center of about the same size next door to the hospital, a children’s hospital, and seven or eight research buildings, all of which have floors underground, in some cases three or four floors underground," says Douglas Gibbs, PhD, a computer systems consultant for the Department of Pathology at the University of Michigan Health System, Ann Arbor. "In my own office, which is two floors underground, I couldn’t get a wireless cell phone modem signal if I had to."

For these and other reasons, Dr. Gibbs says, "we lean toward wireless LAN technology for in-house applications and concentrate more on palm technology for external applications. After working with these technologies for several years, I’d say that for in-house solutions, where you already have an existing LAN, 802.11b wireless LAN options are probably preferable to the various cellular technologies."

Though wireless LANs do afford rapid access to clinical data, they require access points (small antennae) to be deployed throughout the facilities in which they’re used, and wireless network cards have to be installed in any computers used to access them. Most of those cards are still a bit too large to fit into many handheld devices, so accessing wireless LANs is generally practical using only small, subcompact computers. But cards that do fit handheld devices are beginning to come to market.

On the handheld side of this strategy, the process of accessing data poses other challenges besides slow speed. Chief among them is that desktop applications must be adapted to the smaller display area of a personal digital assistant. "What’s the most limiting factor in using a PDA device? It’s the fact that enterprise applications are not written for palmtop devices," says Michael Kramer, MD, an information fellow at the Michigan Collaboratory for Healthcare Information, Department of Internal Medicine, University of Michigan.

When clinical applications are accessed through a Web browser, as many are today, it’s possible to adapt the browser interface to fit on a small screen, a process known as Web clipping. Says Dr. Gibbs: "We’ve pushed out some things like our pathology handbook and our ICD-9 lookup—those were our first forays into Web clipping. Web clipping works well in terms of formatting things so that you get only the information you need and you put it in a format that is fairly readable, even on the Palm."

But even this approach has its limits. "If you scale down your application to a minimal interface, capturing just the most important information in a well-organized menu, where the questions are asked in an intelligent order, then you can potentially use these devices for some minimal clinical capability," says Kenneth Kleinberg, vice president and research director for the Gartner Group’s health care unit, Stamford, Conn. "But you can’t run a full-blown Cerner or IDX application, for example, on a PDA today."

Says Dr. Kramer, "You’ve got to customize your results reporting system to fit on a small screen. And when a physician wants to look at a lab report, he or she wants to see live information, trends, which are fairly sophisticated ways of viewing the data."

Two studies

From September through November 2000, Dr. Kramer directed an inpatient study that involved about 30 interns and the use of either desktop computers or Sharp TriPads, a type of small, light laptop, to access the computerized patient record system at a Veterans Affairs hospital in Ann Arbor. Half of the study participants used a laptop and half used a traditional desktop computer (Kramer J, et al In: Overhage JM, ed. Converging Information, Technology, and Healthcare: Proceedings of the American Medical Informatics Association Symposium, Bethesda, Md., fall 2000).

"We put access points in all of the clinical areas, and configured the network so that physicians could roam from one area to the other," Dr. Kramer says. "We were able to host the computerized patient record application on a wireless network server and then wirelessly transmit the screens and interfaces over the wireless network into the device, so that to the laptop users it appeared as if they were actually sitting at a full desktop computer."

The study led Dr. Kramer to two major observations. "In the inpatient areas the physicians clearly used the wireless system," he says. "In terms of usage statistics, they entered about 20 percent of their orders using the system—the average intern entered something like 1,200 to 1,800 orders a month, which represents significant use of the device and the wireless network."

Dr. Kramer believes that about half of those using laptops enjoyed the mobility it enabled and used it during rounds and at various times during their workday. "About half of them said it actually improved their efficiency and helped them get through their day faster," he says. "The other half either didn’t use it or didn’t find that it was a significant benefit."

The second study, conducted a few months earlier in that same year, examined physician use of the University of Michigan’s clinical information system in an ambulatory setting, also using a wireless LAN and small laptops for access.

"Six physicians who used the device for two weeks went chartless," Dr. Kramer says. "Of those physicians, only one said he could continue mobile." In short, these studies suggest that while mobility is beneficial in the inpatient setting, it may still be problematic in an ambulatory-care setting.

What accounts for this difference? Dr. Kramer points to several possible reasons, including the device itself, the fact that physicians had to carry something from room to room and that they had to also carry paper records—billing sheets, prescription pads, and the variable performance of the wireless server.

"We used a thin client/streaming media computing model," Dr. Kramer says. Streaming technologies, which are often used to transmit video or audio over the Web, operate by buffering-that is, storing-small amounts of content and then transmitting it in a way that seems continuous to the user. However, he says, it is not uncommon for users to experience mild pauses or degradation in quality as they receive, and possibly interact with, these small amounts of buffered content. Similarly, clinicians using the University of Michigan pilot may have, during brief lapses in network performance, experienced modest slowing or delays in their interactions with keyboards, mice, and menus.

One happy user

Other physicians perceive the systems as reliable, indispensable even.

Michigan’s Dr. Laing, who is also associate chair for clinical programs in the Department of Internal Medicine, has been using the university’s wireless LAN system for about a year. With his ultraportable laptop, he has access to everything he could view on a desktop. "There’s nothing I can get on a desktop that I can’t get on this laptop," he says. "There’s less screen real estate, but everything fits just fine, and the resolution on it is quite good."

In fact, Dr. Laing even views the laptop as enhancing his interaction with patients. "It’s better than having a large machine in the room, because it is not intimidating," he says. "The nice thing about it is that you can pull up a chair, sit right next to the patient, and this device becomes your digital assistant if you will, rather than a distraction."

Would he move to a palmtop device instead of the laptop? "Maybe," he says, noting that it would depend on being able to enter data effectively. "The laptops we’re using now are about the smallest thing you can use that has a usable keyboard," he says. "If we could use voice commands instead of a keyboard, that might make a handheld more workable."

What about security?

According to some research groups, a significant number of palmtop computers are lost or stolen each year, perhaps as many as one in 14. If a lost or stolen palmtop holds sensitive patient data, it may suddenly be available to someone not authorized to have it. "When one of our physician users first saw a handheld prescription-writing program," recalls the Gartner Group’s Kleinberg, "one of the first things he said was, ’What if I left it on the desk and somebody picked it up, walked out, and started writing their own prescriptions?’"

Programs do, of course, exist that use password protection and encryption to prevent anyone but the authorized user from accessing PDAs, but they also present potential problems for that user. Anything that forces the legitimate user to log in every time he or she picks up a palmtop computer after taking a break to, say, attend to a patient or take a phone call will not be met with enthusiasm by busy clinicians.

"There are also problems with 802.11 wireless LAN," Kleinberg says. "If anybody wants to intercept that data, it’s not that difficult to do." However, he adds, wireless LANs are used inside a facility, and there is usually some degree of control over who is allowed to gain access to that facility, so simple physical intrusion is a more manageable risk.

What about someone outside the facility? "Sure, someone could come in with a scanning device and overhear information about someone else’s medical condition or concerns," Kleinberg says. "And if you want to add security to a wireless LAN, you can, by a VPN, a virtual private network, encryption, or other application-level security, particularly on Web-based systems." In short, it is possible to overcome the security limits of wireless LANs, particularly in systems that use Web-based software on servers in secure environments.

Toward convergence

"One of the problems with handheld devices is that we end up carrying so many of them," Kleinberg says. "The doc has a PDA, a cell phone, pager—we see the future as one in which all these devices start to come together into one mass-access device."

As that future becomes a reality, it will become possible for clinicians to carry one device that will function as a cell phone and a data-access device. It may be smart enough to know when, for example, it can use the wireless LAN and when it should access the cell phone network. It may support voice recognition, and it will include voice recording for dictation. It will be capable of taking, displaying, and transmitting images, including video.

In this connection, a wireless technology known as Bluetooth is relevant. Developed over the last three years by a consortium led by Ericsson, IBM, Intel, Nokia, and Toshiba, Bluetooth is designed to facilitate and automate interconnectivity among cell phones, palmtops, laptops, printers, digital cameras, and other devices and access points. Bluetooth-capable devices can automatically link and exchange data with one another, making it possible, for example, to automatically update calendar files on a laptop using data from a PDA, with or without the user’s knowledge.

"Things that we just didn’t think were possible or that we laughed at for years are becoming very possible," Kleinberg says. "You can run a video clip now on a Pocket PC, and for those of us who have been around for a while, things like that are just astounding."

* The IEEE 802.11 specification is a wireless LAN standard. Work on the standard began in 1990, passed through half a dozen drafts, and was finalized in 1997. 802.11b covers equipment running up to 11 megabits per second. Sometime this year, 802.11a equipment will become available; the 802.11a specification is intended to support data transmission rates that are twice as fast-or more-as 802.11b equipment.